It is, according to the estate agents, "probably the most valuable plot of land with planning permission to come to the market for sale in Hampstead Village … ever". The Regency-style house now being constructed will provide, behind its electric gates, a cinema, swimming pool and gymnasium and the future owner of this £7m property will be living, we learn, where Constable, and Keats, too, found inspiration.

What the estate agents do not mention is that on this very plot more than seven years ago a murder took place with links to the British government, Chairman Mao and George Bernard Shaw. A killing which was then followed by the first murder trial in Britain in which most of the evidence was heard in secret with the media barred from entering the court.

Now an appeal to the European court of human rights (ECHR) could finally throw a light on the mystery of Downshire Hill.

In June 2006 the body of Allan Chappelow, a reclusive and wealthy retired journalist and author, was found buried beneath a enormous pile of book proofs in his home, No 9 Downshire Hill, close to Hampstead Heath.

Police had gone to the house after being alerted by his bank, HSBC, in the wake of suspicious transactions and his failure to respond to their inquiries. He had been battered to death. Wax found on his body suggested that he might have been tortured.

For years Chappelow, who had worked as a photographer for the Daily Mail and Daily Telegraph, and written books on Shaw, had declined to let anyone enter his house, with the exception of a trusted handyman.

The house was crumbling, the garden wildly overgrown. Detectives found few clues. Unidentified fingerprints could have been Chappelow's; his body was so decomposed it was impossible to take prints from it. There were a few footprints and cigarette ends.

Nearby lived Wang Yam, a Chinese dissident, whose grandfather had been Mao's third in command, while his father had been a Red Army general. Wang had been a research assistant in the Chinese nuclear weapons research institute from 1984 to 1987 and an associate professor at a university in Beijing. He claimed to have been involved in the demonstrations in Tiananmen Square and, supposedly fearful of reprisals, left the country and went, via Hong Kong, to London, where he was very swiftly granted refugee status in 1992.

He worked initially as a researcher at Imperial College and ran his own computer company, Quantum Electronics Corporation, from 1997 till it folded in 1999.

Wang Yam shared a rented house with his girlfriend, Hui Dong. At the time of the murder, he was deeply in debt and being evicted from his flat because of rent arrears.

He came to the attention of the police investigating the murder because, prior to and just after the death of Chappelow, use of the stolen credit cards had been traced to him. Wang had recently left the country for Switzerland where he was arrested in Zug. He was charged with murder, burglary and receiving.

The crown's case was essentially that Wang had stolen mail in order to get access to the victim's accounts, and, quite possibly, had been caught in the act by Chappelow, whom he had then beaten to death.

Much of the trial at the Old Bailey was held in camera, after Jacqui Smith, then home secretary, agreed to requests for secrecy on grounds of national security and "to protect witnesses". Media organisations, including the Guardian, challenged a demand unprecedented in modern times – that witnesses at a&nbsp; forthcoming murder trial should be&nbsp; heard in secret for reasons of national security.

"There have been plenty of trials in the past in which issues have been raised about national security material. It is extremely rare for such cases to be heard in camera," Gavin Millar QC told the trial judge, Mr Justice Ouseley.

He referred to previous cases when allegations about the intelligence agencies had been made in court.

Asked by the judge whether the prosecution would have to drop the case if it did not get a secrecy order, Mark Ellison QC, for the prosecution, replied: "There is a serious possibility the crown may not proceed in this case."

The media were rebuffed and warned not even to speculate as to why the secrecy order was made, and for this reason we are still unable to report the defence case at the trial.

Apart from the clear evidence that Wang had been involved in using the victim's credit card, the other plank of the case against him was that a local postman had seen someone answering his description near the house and that this person had asked about the mail due to be delivered to Chappelow. The postman told this person, who the prosecution alleged must have been Wang, that mail could not be delivered because of foliage in the way of the letterbox; he returned the next day to find the foliage cleared.

In a first trial, in 2008, for which the jury all had to receive security clearance, Wang was convicted of the theft and fraud offences and jailed for four and a half years, but the jury could not agree on the murder charge.

At a second trial he was convicted and jailed for life in 2009 with a recommendation that he serve a minimum of 20 years. He is now in Whitemoor prison, in Cambridgeshire, from where he has contacted the Guardian to protest his innocence.

In his letters, which have also been sent to senior government figures, Wang claims that he had become involved with a criminal gang and that gangsters had been responsible for giving him the stolen cards and cheques. He claims he was unaware of Chappelow's murder at the time he was handling the stolen cards.

Wang's background was confirmed in court by Philip Baker QC, an OBE who was awarded his honour for his work with Chinese political refugees.

He gave evidence for Wang in one of the open sessions of the trial. An appeal against the murder conviction was turned down in 2010. His legal team is now trying to take his case to the ECHR, which led them to court in December to challenge the gagging order.

In a letter from prison, Wang writes: "I believe the only way to my freedom is [to] let public … know what is my defence and what I had done in full picture. No cover-up … I was convicted for murder without even police have evidence that I know the deceased or ever met each other. There is no evidence to link me with the deceased, even police burnt the crime scene by accident and there are unknown DNA fingerprint footprint, all not belong to me."

Wang's case to the ECHR is based on the grounds that he did not have a fair trial because it was not held openly. At the hearing last month in the Royal Courts of Justice, Wang's barrister, Kirsty Brimelow QC, argued that the government was attempting to restrict his access to the ECHR by objecting to in-camera material being presented, even if that material would also be heard in camera. "His right to put his case fully is restricted," she said.

There was reference in court to similar cases of "high sensitivity" and references to CIA complicity in the rendition from Poland of Abd al-Rahim al-Nashiri now held at Guantánamo Bay. It was agreed that "reference to gangsters and the names of those gangsters is not at issue".

The judge said: "The names of the gangsters and what he said they did is material that is perfectly usable by the&nbsp; applicant."

For the crown, James Eadie QC said "the order was made to protect the public interest and the interests of justice … There would be a serious risk of harm in the disclosure of this information".

Mr Justice Ouseley, who reserved judgment, said that "what went on in camera should stay in camera". He noted the presence of a representative of the criminal cases review commission now looking at the case.

Whatever the merits of Wang's defence, a new hearing would answer an important question: was the secrecy request made for genuine reasons of national security or to avoid embarrassment?

• This article was amended on 3 March 2014 to remove a reference to Wang Lijun which described him as former company secretary of the Quantum Electronics Company and an associate of Bo Xilai, who was jailed for corruption offences in China last year. Lijun Wang, who was the company secretary, has asked us to make clear that he has never been an associate of Bo Xilai.

"No one understood better than Stalin that the true object of propaganda is neither to convince nor even to persuade, but to produce a uniform pattern of public utterance in which the first trace of unorthodox thought immediately reveals itself as a jarring dissonance." Leonard Schapiro

Wang's case to the ECHR is based on the grounds that he did not have a fair trial because it was not held openly. At the hearing last month in the Royal Courts of Justice, Wang's barrister, Kirsty Brimelow QC, argued that the government was attempting to restrict his access to the ECHR by objecting to in-camera material being presented, even if that material would also be heard in camera. "His right to put his case fully is restricted," she said.

...

Mr Justice Ouseley, who reserved judgment, said that "what went on in camera should stay in camera". He noted the presence of a representative of the criminal cases review commission now looking at the case.

&nbsp; &nbsp; THE LORD CHIEF JUSTICE:
&nbsp; &nbsp; The applicant is due to be tried before Ouseley J and a jury in the Central Criminal Court on an indictment charging him with the murder of Allan&nbsp; Chappelow&nbsp; and with offences of dishonesty. On 15 January 2008 the judge made an order excluding access of the public to part of the proceeding. The applicant seeks leave to appeal against that order.

"No one understood better than Stalin that the true object of propaganda is neither to convince nor even to persuade, but to produce a uniform pattern of public utterance in which the first trace of unorthodox thought immediately reveals itself as a jarring dissonance." Leonard Schapiro

Police mugshot of Wang Yam, wearing glasses and a goatee beard
Wang Yam argued that because his trial was held in secret, potential witnesses, who might support his story, would not come forward. Photograph: Met Police/PNS

A Chinese dissident convicted of murder after an Old Bailey trial held in secret has lost his attempt to present his whole defence case to the European court of human rights.

The decision comes as potentially significant new evidence has emerged – a potential new witness – as a result of a Guardian report on the case last month.

Wang Yam, the grandson of Chairman Mao's third in command, fled China and was granted refugee status in Britain in 1992. In 2009 he was convicted of the murder of Allan Chappelow, 86, a retired journalist found battered to death in his home in Hampstead, north London.

The prosecution suggested that Yam had stolen bank details from Chappelow's mailbox and had possibly been caught in the act by Chappelow, whom he had then beaten to death. His defence case was held in camera on the grounds of "national security" and the media were barred from reporting it or even speculating on what it might be. He was convicted after a retrial and jailed for life.

In an application to lift the gagging order so that his defence could be presented in full, Yam claimed that he did not receive a fair trial because of the secrecy. He argued that potential witnesses, who might support his story, would not come forward.

In his written judgment published , Mr Justice Ouseley, the original trial judge, declined to vary the gagging order.

The judgment states: "I acknowledge that a court should not stand in the way of what an applicant wishes to place before Strasbourg, unless there is very good reason to do so. I have no doubt that there are very good reasons to do so in this case." He added that "the protected interests included national security and the protection of the identity of a witness or other person".

The judgment continues: "Wang Yam's name was in the public domain as were the names of the gangsters whom he alleged were responsible for the theft of the deceased's identity. It is impossible to imagine that the gangsters Wang Yam claimed to have dealt with would have come forward, and it is pure speculation that a third party would have come forward because of any greater publicity."

Following publication of a Guardian report on the case last month, a potential new witness has emerged. A former neighbour of the murdered man told the Guardian: "I lived a few doors down from [Chappelow's house] back in 2006. The following February, [when Yam was already in custody] I was in our house and hear a rustling in our porch. I opened the door to find a man with a knife going through our post. He pointed the knife at me and I shut the door … He said if I called the police he would kill them."

The neighbour called the police, who advised him to change his bank details. "It is clear to me that there was a violent person or gang operating in the street and the lack of police interest was very bizarre." The former neighbour has now given a statement to Yam's lawyers.

Commenting on Thursday's decision, Yam's barrister, Kirsty Brimelow QC, said: "The UK government's position amounts to a lack of trust in the judges of ECHR. As the UK ratified the European convention, this approach is disappointing."

Yam's solicitors, Janes, said they were considering what steps should now be taken. The case is also being reviewed by the Criminal Cases Review Commission, a spokesman confirmed on Thursday.

"No one understood better than Stalin that the true object of propaganda is neither to convince nor even to persuade, but to produce a uniform pattern of public utterance in which the first trace of unorthodox thought immediately reveals itself as a jarring dissonance." Leonard Schapiro

A man convicted of murdering a reclusive author in his Hampstead home will have his case heard at the Court of Appeal because of alleged police failings.

Wang Yam was convicted for the murder of Allen Chappelow, but has always maintained his innocence.

Mr Chappelow, who was 87 when he died in 2006, was found dead in his Downshire Hill home.

Yam also denied related charges of burglary, handling stolen property and obtaining a money transfer by deception at a trial in 2008.

Yam was convicted of handling stolen property, obtaining a money transfer by deception and theft, but the jury were unable to reach a verdict on charges of murder and burglary.

Following a retrial Mr Yam was convicted of murder and burglary and was sentenced to life imprisonment with a minimum prison term of 20 years.

Yam appealed in 2010.

The handling stolen goods conviction was quashed, but all other appeals were dismissed.

Yam applied to the Criminal Cases Review Commission for a review of his conviction in July 2012.

Having conducted a comprehensive investigation of the case, the Commission has decided to refer Mr Yam’s murder conviction to the Court of Appeal.

A statment from the Criminal Cases Review Commission said: “The referral is based on new evidence relating to the failure by police to reveal to the Crown Prosecution Service, and consequently to deprive Mr Yam’s defence of, material which might have assisted the defence and /or undermined the prosecution case.

“The material in question relates to police records about an incident which took place near to, and within months of, Mr Chappelow’s murder in which someone was threatened in circumstances with features relevant to the case against Mr Yam.

“The incident arguably could have formed the basis for the defence to propose the existence of alternative suspect.”

ï¿½To those who are afraid of the truth, I wish to offer a few scary truths; and to those who are not afraid of the truth, I wish to offer proof that the terrorism of truth is the only one that can be of benefit to the proletariat.ï¿½ -- On Terrorism and the State, Gianfranco Sanguinetti

Murdered reclusive millionaire author Allan Chappelow Picture: Metropolitan Police
Chinese dissident Wang Yam who is serving a life sentence for the murder of reclusive author Mr Chappellow in his home in Downshire Hill, Hampstead has lost his long battle to overturn his conviction.

Yam was found guilty at the Old Bailey in 2009 of beating 86-year-old Allan Chappelow to death.

The 55-year-old challenged his conviction at the Court of Appeal, in London, with his lawyers arguing there was “fresh evidence” capable of casting doubt on its safety.

But his appeal was rejected by the court with Lord Chief Justice Thomas saying the evidence from three new witnesses for the defence did not undermine the jury’s verdict.

Mr Chappelow, was repeatedly hit over the head at his crumbling Georgian terraced house in May 2006. His body was found weeks later under a metre-high pile of papers after police were alerted by suspicious bank transactions on his account.

He had suffered massive head injuries and his wounds indicated he was possibly tortured.

Use of his stolen credit cards was traced to Yam, a financial adviser who lived in nearby Denning Road, Hampstead, and had fled to Switzerland.

Yam, who left China after the 1989 Tiananmen Square uprising, always denied the murder and blamed gangsters.

At his first trial in 2008, Yam was found guilty of theft and fraud and jailed for four-and-a-half years, but the jury was unable to reach a decision on the murder charge.

He was convicted of murder the following year and jailed for a minimum of 20 years.

His defence case was heard behind closed doors at the insistence of prosecutors, after the government claimed secrecy was necessary in the interests of national security. It is believed to be the first murder trial in which a secrecy order was imposed for such a reason.

Yam’s appeal was dismissed by Lord Thomas who said: “The evidence at trial sufficiently convinced the jury that Yam was solely and exclusively responsible for the activities involving the deceased’s handset/SIM card and their use in the identity fraud and that the connection between those activities and the death of Allan Chappelow established Yam as the only possible perpetrator of the murder.”

Yam, now in his 50s, has also launched a case before the European Court of Human Rights, challenging the secret nature of his trial.

"The problem with always being a conformist is that when you try to change the system from within, it's not you who changes the system; it's the system that will eventually change you." -- Immortal Technique

"The media is the most powerful entity on earth. They have the power to make the innocent guilty and to make the guilty innocent, and that's power. Because they control the minds of the masses." -- Malcolm X

"The eternal fight is not many battles fought on one level, but one great battle fought on many different levels." -- The Antagonist

In some ways she was far more acute than Winston, and far less susceptible to Party propaganda. Once when he happened in some connection to mention the war against Eurasia, she startled him by saying casually that in her opinion the war was not happening. The rocket bombs which fell daily on London were probably fired by the Government of Oceania itself, "just to keep the people frightened." -- George Orwell, 1984